Rational approximation of fractional order systems using Carlson method

Fractional order systems can be modeled more adequately using fractional calculus theory rather than integer calculus. Since fractional order system is an infinite dimensional filter, proper approximation of the infinite dimensional operator s±a with (0 <; α <; 1, α ϵ R) by finite order rational transfer function is fundamentally important. This is required to study the dynamical behavior of fractional order systems. In this paper, Carlson method is applied for modeling the fractional order operator a into approximated integer order models. The analysis is performed for different values of a. Simulations have been performed in MATLAB and comparisons presented to validate the effectiveness of the proposed models. These models can be used for realization of fractional order systems.